(3R,6R,12R,20S,24S)-3,6,12-Triacetyl-20,24-ep-oxy-dammarane-3,6,12,25-tetra-ol.

The title compound, C(36)H(58)O(8), was prepared from 20(S)-protopanaxatriol, which was degraded from Panax quinquefolium saponin with sodium in glycerine, extracted and seperated by flash chromatography. Three six-membered rings are in chair conformations, the five-membered ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and envelope. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, and C-H⋯O contacts also occur. The absolute structure was assigned on the basis of the synthesis.